| // Copyright 2017 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "quiche/http2/hpack/decoder/hpack_decoder.h" |
| |
| #include "quiche/http2/decoder/decode_status.h" |
| #include "quiche/common/platform/api/quiche_flag_utils.h" |
| #include "quiche/common/platform/api/quiche_logging.h" |
| |
| namespace http2 { |
| |
| HpackDecoder::HpackDecoder(HpackDecoderListener* listener, |
| size_t max_string_size) |
| : decoder_state_(listener), |
| entry_buffer_(&decoder_state_, max_string_size), |
| block_decoder_(&entry_buffer_), |
| error_(HpackDecodingError::kOk) {} |
| |
| HpackDecoder::~HpackDecoder() = default; |
| |
| void HpackDecoder::set_max_string_size_bytes(size_t max_string_size_bytes) { |
| entry_buffer_.set_max_string_size_bytes(max_string_size_bytes); |
| } |
| |
| void HpackDecoder::ApplyHeaderTableSizeSetting(uint32_t max_header_table_size) { |
| decoder_state_.ApplyHeaderTableSizeSetting(max_header_table_size); |
| } |
| |
| bool HpackDecoder::StartDecodingBlock() { |
| QUICHE_DVLOG(3) << "HpackDecoder::StartDecodingBlock, error_detected=" |
| << (DetectError() ? "true" : "false"); |
| if (DetectError()) { |
| return false; |
| } |
| // TODO(jamessynge): Eliminate Reset(), which shouldn't be necessary |
| // if there are no errors, and shouldn't be necessary with errors if |
| // we never resume decoding after an error has been detected. |
| block_decoder_.Reset(); |
| decoder_state_.OnHeaderBlockStart(); |
| return true; |
| } |
| |
| bool HpackDecoder::DecodeFragment(DecodeBuffer* db) { |
| QUICHE_DVLOG(3) << "HpackDecoder::DecodeFragment, error_detected=" |
| << (DetectError() ? "true" : "false") |
| << ", size=" << db->Remaining(); |
| if (DetectError()) { |
| QUICHE_CODE_COUNT_N(decompress_failure_3, 3, 23); |
| return false; |
| } |
| // Decode contents of db as an HPACK block fragment, forwards the decoded |
| // entries to entry_buffer_, which in turn forwards them to decode_state_, |
| // which finally forwards them to the HpackDecoderListener. |
| DecodeStatus status = block_decoder_.Decode(db); |
| if (status == DecodeStatus::kDecodeError) { |
| ReportError(block_decoder_.error()); |
| QUICHE_CODE_COUNT_N(decompress_failure_3, 4, 23); |
| return false; |
| } else if (DetectError()) { |
| QUICHE_CODE_COUNT_N(decompress_failure_3, 5, 23); |
| return false; |
| } |
| // Should be positioned between entries iff decoding is complete. |
| QUICHE_DCHECK_EQ(block_decoder_.before_entry(), |
| status == DecodeStatus::kDecodeDone) |
| << status; |
| if (!block_decoder_.before_entry()) { |
| entry_buffer_.BufferStringsIfUnbuffered(); |
| } |
| return true; |
| } |
| |
| bool HpackDecoder::EndDecodingBlock() { |
| QUICHE_DVLOG(3) << "HpackDecoder::EndDecodingBlock, error_detected=" |
| << (DetectError() ? "true" : "false"); |
| if (DetectError()) { |
| QUICHE_CODE_COUNT_N(decompress_failure_3, 6, 23); |
| return false; |
| } |
| if (!block_decoder_.before_entry()) { |
| // The HPACK block ended in the middle of an entry. |
| ReportError(HpackDecodingError::kTruncatedBlock); |
| QUICHE_CODE_COUNT_N(decompress_failure_3, 7, 23); |
| return false; |
| } |
| decoder_state_.OnHeaderBlockEnd(); |
| if (DetectError()) { |
| // HpackDecoderState will have reported the error. |
| QUICHE_CODE_COUNT_N(decompress_failure_3, 8, 23); |
| return false; |
| } |
| return true; |
| } |
| |
| bool HpackDecoder::DetectError() { |
| if (error_ != HpackDecodingError::kOk) { |
| return true; |
| } |
| |
| if (decoder_state_.error() != HpackDecodingError::kOk) { |
| QUICHE_DVLOG(2) << "Error detected in decoder_state_"; |
| QUICHE_CODE_COUNT_N(decompress_failure_3, 10, 23); |
| error_ = decoder_state_.error(); |
| } |
| |
| return error_ != HpackDecodingError::kOk; |
| } |
| |
| void HpackDecoder::ReportError(HpackDecodingError error) { |
| QUICHE_DVLOG(3) << "HpackDecoder::ReportError is new=" |
| << (error_ == HpackDecodingError::kOk ? "true" : "false") |
| << ", error: " << HpackDecodingErrorToString(error); |
| if (error_ == HpackDecodingError::kOk) { |
| error_ = error; |
| decoder_state_.listener()->OnHeaderErrorDetected( |
| HpackDecodingErrorToString(error)); |
| } |
| } |
| |
| } // namespace http2 |